07 May 2016

Bali's next big Tsunami

The head for Earthquakes and Tsunamis at the Meteorology, Climate and Geophysics Agency (BMKG), recently told that Bali is at high risk of a major earthquake. Bali has a long history of earthquakes that have cost lives and resulted in major property damage. The potential for earthquakes remains high because Bali is positioned between two sources of quakes. In North of Bali is the Flores Back Arc Thrust Belt while to the south is the subduction zone separating the Indo-Australian Plate and the Eurasian Plate. Those living in the north of Bali may have less than 5 minutes to seek high ground against a tsunami following an earthquake. People living in Bali’s south, aided by tsunami sirens, may have as much as 30 minutes to seek the safety of higher ground.  Bali has suffered catastrophic earthquakes resulting in substantial loss of life in 1817, 1857 and 1917. Some have speculated that an earthquake-prone area will experience a major seismic event on an average of once every one hundred years, which could mean Bali is ready for its next major quake at any time. A 1974 earthquake that struck Seririt in the regency of Buleleng, North Bali, killed an estimated 573 people and left nearly 5,000 people injured. Despite the high loss of life, this Seririt earthquake affected a fairly limited geographical region. Not every earthquake creates a tsunami. To generate a tsunami an earthquake must generally measure above 7.0 on the Richter scale, create a vertical fracture and occur at a relatively shallow depth. Bali is divided into three zones most at risk of earthquakes. Zone 1: Comprised of the regencies of Klungkung, Bangli and Karangasem. Zone 2: Comprised of the regencies of Tabanan, Jembrana and the City of Denpasar. Zone 3: Comprised of the regencies of Badung and Gianyar. Bali has 9 tsunami warning sirens in operation and have asked for 10 more sirens to be installed by the Central Government. Recent news reports, however, state that all the warning buoys that trigger the sirens ashore are no longer in operating order.

No comments:

Post a Comment